So it is gone after the prologue for the people that have done it? Otherwise that just does not make sense.Incidentally, for those testing it by going back AFTER finishing the prologue, I suspect that it may not be possible then "by design", as you see the Wild Hunt destroy the shrine during the chase at the end of the prologue.
So this was over 4 months ago and the bug still persists. Any word on this please? Give us a siiiign! ; ;Firstly thank you very much for your reports. We are aware of the issue and we will investigate so we can fix it soon : ) Please report any POI that has issue with spawning and we will check if there are any issues.
Possible solution for now is to save and load the game. Please to that while being not in sight of the POI. Also meditating at the site won't help as for mechanics reasons (so that player will not be attacked while meditating) monsters will not spawn near meditating player.